1. Field of the Invention
The present invention generally relates to a semiconductor integrated circuit (IC) device and a mobile terminal equipped with that IC device and, more specifically, to an effective technique for applying flash memory and electrically erasable programmable read-only memory (EEPROM) configurations in the semiconductor IC device.
2. Discussion of Background
FIG. 1 is an example block diagram of functions of an integrated circuit (IC) device. A microcomputer 1 which is an example of a semiconductor IC device is made up of a CPU (Central Processing Unit) 2, a set of memories consisting of a ROM (Read Only Memory) 4, an SRAM (Static Random Access Memory) 5, and an EEPROM (Electrically Erasable Programmable Read Only Memory) 6, an I/O port 10 to interface with an external device, a clock generation circuit 8 to supply clocks to the CPU 2 and other circuits, a timer 3 for time control over a system timer and the memory circuits, a system control logic 9, a co-processor 7, an address bus 11, a data bus 12, and other components.
In general, a boot program for starting up the CPU 2 and application software are stored in the ROM 4. Diverse types of data that may be rewritten at a high frequency are stored in the EEPROM 6 that enables data rewriting in units of bytes. Taking an example of an IC card chip built in a mobile phone, data such as telephone numbers, charging information, and call memorandums are stored in the EEPROM 6. Unfortunately, time consumed for debugging software tends to make it hard to shorten a turn around time (TAT).